BTEX in indoor air of barbershops and beauty salons: Characterization, source apportionment and health risk assessment.

BACKGROUND: Volatile organic compounds, mainly BTEX, are among the pollutants of concern in beauty salons and barbershops that threaten both staff personnel and clients' health. This study aimed to determine the concentration of BTEX in barbershops and beauty salons and assess the carcinogenic and non-carcinogenic risks based on the actual risk coefficients. Also, possible sources of BTEX were determined. METHOD: Samples were collected by passive sampling. Quantitative and qualitative measurements of BTEX compounds were performed using gas chromatography-mass spectrometry (GC-MASS). Subsequently, the health risks were assessed according to the US Environmental Protection Agency. SPSS24 software and positive matrix factorization (PMF) analysis were used for statistical analysis and source apportionment respectively. RESULTS: Toluene is the most abundant compound in beauty salons, with a maximum concentration of 219.4 (µg/m3) in beauty salons. Results indicated that the mean ELCR value estimated for benzene regarding female staff exposure (1.04 × 10-5) was higher than that for men (4.05 × 10-6). Also, ELCR values of ethylbenzene for staff exposure were 2.08 × 10-6 and 3.8 × 10-6 for men and women, respectively, and possess possible carcinogenesis risks. CONCLUSION: Use of solvents and cosmetic products, improper heating systems, and type of service are the sources that probably contribute to BTEX emissions in beauty salons. It is necessary to follow health guidelines and conduct continuous monitoring for their implementation, in addition to setting a mandated occupational regulation framework or air quality requirements, to improve the health conditions in beauty salons.

Analysis of heavy metal, rare, precious, and metallic element content in bottom ash from municipal solid waste incineration in Tehran based on particle size.

Waste incineration is increasingly used worldwide for better municipal solid waste management and energy recovery. However, residues resulting from waste incineration, such as Bottom Ash (BA) and Fly Ash (FA), can pose environmental and human health risks due to their physicochemical properties if not managed appropriately. On the other hand, with proper utilization, these residues can be turned into valuable Municipal metal mines. In this study, BA was granulated in various size ranges (< 0.075 mm, 0.075-0.125 mm, 0.125-0.5 mm, 0.5-1 mm, 1-2 mm, 2-4 mm, 4-16 mm, and > 16 mm). The physicochemical properties, heavy metal elements, environmental hazards, and other rare and precious metal elements in each Granulated Bottom Ash (GBA) group from Tehran's waste incineration were examined using ICP-MASS. Additionally, each GBA group's mineralogical properties and elemental composition were determined using X-ray fluorescence (XRF) and X-ray diffraction (XRD). The results showed that the average concentration of heavy metals in GBA, including Zn (1974 mg/kg), Cu, and Ba (790 mg/kg), Pb (145 mg/kg), Cr (106 mg/kg), Ni (25 mg/kg), Sn (24 mg/kg), V (25 mg/kg), As (11 mg/kg), and Sb (29 mg/kg), was higher in particles smaller than 4 mm. Precious metals such as gold (average 0.3 mg/kg) and silver (average 11 mg/kg) were significantly higher in GBA particles smaller than 0.5 mm, making their extraction economically feasible. Moreover, rare metals such as Ce, Nd, La, and Y were detected in GBA, with average concentrations of 24, 8, 11, and 7 mg/kg, respectively. The results of this study indicated that BA contains environmentally concerning metals, as well as rare and precious metals, with high concentrations, especially in particles smaller than 4 mm. This highlights the need for proper pre-treatment before using these materials in civil and municipal applications or even landfilling.

Polycyclic aromatic hydrocarbons (PAHs) in meat, poultry, fish and related product samples of Iran: a risk assessment study.

Meat, poultry, and seafood such as fish are a valuable source of protein, vitamins and minerals. Considering their high consumption in the human diet, it is necessary to study pollutants (such as PAHs) in them. This present study has focused on the PAHs level and probabilistic risk of health in meat, poultry, fish and related product samples by MSPE-GC/MS technique (magnetic solid-phase extraction with gas chromatography-mass spectrometry). The maximum mean of 16 PAH was detected in smoked fish samples (222.7 ± 13.2 µg/kg) and the minimum mean of 16 PAH was detected in chicken (juje) kebab (112.9 ± 7.2 µg/kg µg/kg). The maximum mean of 4PAHs was detected in tuna fish (23.7 ± 2.4 µg/kg) and the minimum mean of 4PAHs was seen in grilled chicken and sausage samples (non-detected). Our results showed the 4PAHs and B[a]P were lower than the EU (European Union) standard levels (these standard levels were 30 and 5 µg/kg, respectively). Furthermore, the correlation among the type and concentrations of PAHs congeners was investigated through cluster analysis by heat map and principal component analysis. The 90th percentile ILCR (incremental lifetime cancer risk) of PAH compounds in fish, poultry, meat and related products samples was 3.39E-06, which was lower than the maximum acceptable level of risk (10-4). Finally, the highest ILCR was related to hamburger (4.45E-06). Therefore, there is no risk in consuming these foods in Iran, but it is necessary to monitor PAHs concentration in different types of foods.

4-Chlorophenol adsorption from water solutions by activated carbon functionalized with amine groups: response surface method and artificial neural networks.

4-Chlorophenol pollution is a significant environmental concern. In this study, powdered activated carbon modified with amine groups is synthesized and investigated its efficiency in removing 4-chlorophenols from aqueous environments. Response surface methodology (RSM) and central composite design (CCD) were used to investigate the effect of different parameters, including pH, contact time, adsorbent dosage, and initial 4-chlorophenol concentration, on 4-chlorophenol removal efficiency. The RSM-CCD approach was implemented in R software to design and analyze the experiments. The statistical analysis of variance (ANOVA) was used to describe the roles of effecting parameters on response. Isotherm and kinetic studies were done with three Langmuir, Freundlich, and Temkin isotherm models and four pseudo-first-order, pseudo-second-order, Elovich, and intraparticle kinetic models in both linear and non-linear forms. The synthesized adsorbent was characterized using X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses. The results showed that the synthesized modified activated carbon had a maximum adsorption capacity of 316.1 mg/g and exhibited high efficiency in removing 4-chlorophenols. The optimal conditions for the highest removal efficiency were an adsorbent dosage of 0.55 g/L, contact time of 35 min, initial concentration of 4-chlorophenol of 110 mg/L, and pH of 3. The thermodynamic study indicated that the adsorption process was exothermic and spontaneous. The synthesized adsorbent also showed excellent reusability even after five successive cycles. These findings demonstrate the potential of modified activated carbon as an effective method for removing 4-chlorophenols from aqueous environments and contributing to developing sustainable and efficient water treatment technologies.

Occurrence and removal of psychiatric pharmaceuticals in the Tehran South Municipal Wastewater Treatment Plant.

Psychiatric drugs released by humans in wastewater have received more attention because of their potential risks for aquatic organisms. In this study, the occurrence of the two most common groups of psychiatric drugs (sedatives-hypnotics-anxiolytics and antidepressants) were evaluated in the Tehran South Municipal Wastewater Treatment Plant. All the target sedatives-hypnotics-anxiolytics (alprazolam, phenobarbital, and thioridazine) and antidepressants (fluoxetine, citalopram, sertraline, and venlafaxine) were observed in influent and secondary clarification (SC) effluent. Thioridazine (164.25 ± 218.74 ng/L) and citalopram (672.53 ± 938.56 ng/L) had the highest mean concentrations in the influent, while alprazolam (5.09 ± 2.33 ng/L) and citalopram (776.97 ± 1088.01 ng/L) had the highest concentrations in the SC effluent. The higher concentrations of the psychiatric drugs, except thioridazine, were detected in the SC effluent compared to the concentrations in the influent. The increased drugs concentrations, with negative removal efficiencies, were more distinctive in the cold season samples. Psychiatric drugs processed in the chlorination unit followed a completely different pattern compared to the drugs in the biological treatment unit. All the drugs' concentrations, except thioridazine, decreased in the chlorination unit, ranging between 27 ± 14% for alprazolam and 75 ± 10% for citalopram. However, the mean concentrations of the detected drugs were as follows: sertraline (11.96 ± 11.62 ng/L) and venlafaxine (184.94 ± 219.74 ng/L) which could cause environmental and ecological concerns.

Combination of advanced nano-Fenton process and sonication for destruction of diclofenac and variables optimization using response surface method.

Diclofenac (DCF) as a non-steroidal pharmaceutical has been detected in aquatic samples more than other compounds due to its high consumption and limited biodegradability. In this study, ultrasound waves were applied along with an advanced nano-Fenton process (US/ANF) to remove DCF, and subsequently, the synergistic effect was determined. Before that, the efficiency of the US and ANF processes was separately studied. The central composite design was used as one of the most applicable responses surface method techniques to determine the main and interactive effect of the factors influencing DCF removal efficiency in US/ANF. The mean DCF removal efficiency under different operational conditions and at the time of 1-10 min was obtained to be about 4%, 83%, and 95% for the US, ANF, and US/ANF, respectively. Quadratic regression equations for two frequencies of US were developed using multiple regression analysis involving main, quadratic, and interaction effects. The optimum condition for DCF removal was obtained at time of 8.17 min, H/F of 10.5 and DCF concentration of 10.12 at 130 kHz US frequency. The synergy index values showed a slight synergistic effect for US/ANF (1.1). Although the synergistic effect of US/ANF is not very remarkable, it can be considered as a quick and efficient process for the removal of DCF from wastewater with a significant amount of mineralization.

Capability of Different Multi-Criteria Decision-Making Techniques in the Performance Assessment of the Hospitals in Terms of Medical Waste Management.

Background: Assessing the performance of hospitals in waste management requires considering several criteria of different types. The multiplicity of the criteria and how they are weighed and, ultimately, the ranking of hospitals; are among the most complex challenges faced by the environmental health authorities. This research tried to assess the capability of four commonly used multi-criteria decision-making methods, as well as a hybrid technique for performance assessment of six hospitals in Tehran City, Iran, in 2018 regarding waste management. Methods: The effective criteria and sub-criteria were identified by reviewing the relevant literature. The data collection tool was a self-constructed checklist developed based upon the identified criteria and sub-criteria and analysis of the collected data was done in MATLAB software. The sample hospitals were ranked based on the scores given to the management performance of hospitals. Results: The final rankings by the different techniques did not differ significantly. According to the results of the hybrid method, among six studied hospitals, the top three hospitals were Hospital C, B, and A respectively, regarding hospital waste reduction criteria. These hospitals generally had an acceptable performance in terms of waste management, especially waste disinfection and separation at the origin. Conclusion: In assessing the performance and ranking of hospitals in terms of waste management, hybrid multi-criteria decision-making techniques can be used as a useful tool in waste management planning. By identifying the areas in need of corrective actions and choosing the appropriate strategy, they pave the way for improving the performance of hospitals in the field of waste management.

Quantifying and qualifying hospital pharmaceutical waste: a case study in Tehran, Iran.

Nowadays, hospital waste management is particularly important due to its potential pathogenicity and serious hazards and is considered as one of the most important environmental problems. One of the prominent actions in hospital waste management is quantitative studies and the collection of reliable and valid data to provide the best management solutions using the obtained information. Therefore, the present study was performed to reach this purpose. Measuring and quantifing of the hospital waste was performed using a daily list of the amount of medication used in the hospital. The weight of vial containers and the amount of residue and syringe, and serum wastes were also measured separately. Finally, the overall amount and per capita of waste production were determined. The results showed that pharmaceutical waste and drug residue in the hospital were 153.82 kg.d-1 and 45.87 kg.d-1, respectively. Per capita production of pharmaceutical waste per patient and hospital bed was estimated to be 181.81 g.p-1.d-1 and 264.7 g.b-1.d-1, and per capita production of drug residue per patient and hospital bed were 54.22 g.p-1.d-1 and 88.21 g.b-1.d-1, respectively. Among the types of pharmaceutical waste found in vials, the antibiotics had the highest weight percent. The emergency department and operating room played a major role in producing pharmaceutical waste among different hospital wards. This study showed that the pharmaceutical waste production in the considered hospital was relatively high, which can be attributed to several factors such as waste management, type of health care, type of hospital, ratio of patients under daily treatment, gender, and initial weight of containers. Supplementary Information: The online version contains supplementary material available at 10.1007/s40201-022-00790-6.

Status of TNF-α and IL-6 as pro-inflammatory cytokines in exhaled breath condensate of late adolescents with asthma and healthy in the dust storm and non-dust storm conditions.

Exposure to airborne particulate matter (PM) can be considered as an important risk factor for human health. Some cytokines have been recognized as the biomarkers of exposure to air pollution. Experimental studies indicate that PM exposure could be associated with inflammation. Thus, the purpose of this study was to evaluate whether the exposure to air PM is associated with biomarkers of inflammation. The specific aim of this study was to determine the correlation between airborne PM levels and IL-6 and TNF-α as airway inflammation biomarkers among two groups of late adolescents in northwest of Iran. This study included 46 subjects, comprising 23 asthmatic subjects and 23 non-asthmatic persons. Environmental PM (PM10, PM2.5 and PM1) levels were measured in dust storm and non-dust storm days during both cold and warm seasons. Following the sampling of PM, Two pro-inflammatory cytokines of IL-6 and TNF-α in exhaled breath condensate (EBC) were also determined in the EBC samples via commercial ELISA kits. Daily mean ambient air PM10, PM2.5 and PM1 concentrations during the dust storm days was 221.79, 93.13 and 25.52 µg m-3 and in non-dusty days 48.37, 18.54 and 6.1 µg m-3, respectively. Biomarkers levels were significantly (p < 0.001) higher in asthmatic students compared to the non-asthmatic subjects. EBC cytokines levels were increased in dust storm days compared to the non-dusty days (p < 0.001) and were positively correlated with different size of ambient PM concentration. Dust storm conditions can increase the pro-inflammatory cytokines and cause adverse effects on pulmonary health and lung tissue damage.

The analysis and probabilistic health risk assessment of polycyclic aromatic hydrocarbons in cereal products.

The analysis and probabilistic health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in cereal products were done by using magnetic solid-phase extraction (MSPE) method and gas chromatography/mass spectrometric (GC/MS). The results of method showed LOQ and LOD of PAHs compounds were 0.105-0.180 and 0.035-0.060 µg/kg, and the recorded values were 4.3-12.1 and 6.1-20.3% for repeatability and reproducibility with an estimated recovery of 94.4-103.4%. In this study, we analyzed kind of bread (Barbari, Sangak, Baguette, Taftoon, Lavash), macaroni, lasagna, and cooked rice that mean of total PAHs were 98.2, 121.7, 134.9, 166.3, 176.3, 176.2, 130.1, and 248.3 µg/kg, respectively. Further, the correlation between the type and amount of 16 PAHs with cereal products samples evaluated with multivariate principal component analysis and heat map visualization. The highest incremental lifetime cancer risk (ILCR) was found in cooked rice (7.80E-6), while the lowest ILCR was found in Lasagna (2.35E-07). In conclusion, the PAHs content in the tested products were in low health risk ranges (1 × 10-6 < ILCR < 1 × 10-4), and all of the cereal products sold in Tehran are considered safe for consumers. Therefore, cereal products should be regularly evaluated and monitored by regulatory agencies to reduce contaminants in these high-consumption products.

Bottled water quality ranking via the multiple-criteria decision-making process: a case study of two-stage fuzzy AHP and TOPSIS.

Access to healthy drinking water is vital to human health and development. Bottled water consumption has been on the rise in recent years. As several chemical and bacteriological parameters affect bottled water quality, it is difficult to choose the highest-quality bottled water. Numerous studies have proposed the use of multiple-criteria decision-making (MCDM) methods to overcome this problem. Herein, the two-stage fuzzy analytic hierarchy process (FAHP) and technique for order preference by similarity to ideal solution (TOPSIS) method were adopted to rank different brands of bottled water. The FAHP approach allows working at the intervals of judgment rather than absolute values. TOPSIS is a technique for ordering performance based on its similarity to the ideal solution. An expert panel selected and classified the criteria and sub-criteria. A pairwise comparison questionnaire was then developed, and the weights of the criteria and sub-criteria were assigned by water quality experts. The data on the quality of different brands of water were collected from the Iranian bottled water database. The final data analysis and weight determination of each parameter were performed in Excel and R software Programs. Finally, the CCi (value of closeness coefficient) and rank of 71 bottled water brands were calculated, and the best brand was introduced. Among the selected criteria, carcinogenic chemical compounds with the weight of 0.368 were the most important compound in ranking bottled water brands, followed by bacteriologic, pathogenic chemical compounds, chemical compounds important in terms of toxicity, nutritious chemical compounds with a low toxicity level, chemical compounds related to esthetic effects, and chemical compounds without health effects, respectively.

Correction to: Evaluation of iron and manganese removal effectiveness by treatment plant modules based on water pollution index; a comprehensive approach.

[This corrects the article DOI: 10.1007/s40201-021-00665-2.].

Antibiotic resistance and antibiotic-resistance genes of Pseudomonas spp. and Escherichia coli isolated from untreated hospital wastewater.

Hospitals are considered an important factor in the spread of antibiotic-resistant bacteria (ARBs) and antibiotic-resistance genes (ARGs). The purpose of this research was to characterize the microbial populations in hospital wastewater and investigated the prevalence of ß-lactamase, SulІ and QnrS resistance genes. In the first step, culture method was used to isolate Pseudomonas aeruginosa and Escherichia coli. In the next step, accurate identification of isolated bacteria was carried out using the polymerase chain reaction (PCR) method, then the resistance of the bacteria at different concentrations of antibiotics (8-128 µg/mL) was examined. Finally the ARGs were detected using the PCR method. The averages of heterotrophic plate count (HPC) and ARB concentration in wastewater samples were 1.8 × 108 and 4.3 × 106 CFU/100 mL, respectively. The highest resistance rates were found for sulfamethoxazole and the highest resistance rates in the ß-lactamase group were for ceftazidime, while highest sensitivity was for gentamicin and there was no isolate that was sensitive to the studied antibiotics. SulІ and QnrS were the highest and lowest abundance of all ARGs in samples respectively and blaSHV was the highest ß-lactam resistance gene. Our results indicated an increase in the resistance of identified bacteria to several antibiotics. So it can be concluded that numerous antibiotic-resistant pathogens and vast numbers of ARGs exist in the human body so that their release from hospitals without effective treatment can cause many dangers to the environment and human health.

Evaluation of iron and manganese removal effectiveness by treatment plant modules based on water pollution index; a comprehensive approach.

Groundwater is a viable alternative when access to surface water resources is limited. Iron and manganese are known ions in soil and naturally in groundwater sources. However, human activities also are responsible. To identifying the best module for removing manganese and iron in the water treatment plant (WTP) of Mazandaran, 516 samples were taken from raw and treated water. The concentration of manganese, iron, was measured by atomic absorption spectrophotometry, and turbidity was used with the nephelometry method. The water pollution index (WPI) was applied for categorizing the status of pollution in treated water. The effect of seasonal temperature and backwashing (At flow rates of 3.5, 9.2, and 15.3 m h-1) on the sand filter efficiency was also investigated. The highest concentrations of manganese, iron, and turbidity in raw water were 0.744, 6.70 mg L-1, and 41.8 NTU, and in treated water were 0.67, 1.09 mg L-1, and 5.58 NTU, respectively. The mean concentration of manganese and iron in raw and treated water were 0.24 ± 0.1, 0.93 ± 0.91, 0.105 ± 0.06 and 0.18 ± 0.14 mg L-1 respectively. The WPI statuses in drinking water were excellent for manganese and iron in 95.74 and 53.88 % of the samples and very poor in 1.16 and 12.01 % of the samples, respectively, and its classification for drinking water for manganese and iron was excellent ˃ good ˃ extremely polluted ˃ polluted and the concentration of iron was more than manganese in treated water. The study of temperature's effect on sand filters showed that the removal efficiency in warm seasons was higher than in cold seasons. Also, the turbulence in the backwash with the 9.2 m h- 1 rates, is lesser than other speeds, and in this flow, after 270 s, the turbidity decreases to less than 10 NTU. Spearman correlation comparison showed that the parameters amounts after filtration decreased significantly (p ≤ 0.0001) in comparison to raw water. The results showed that module #1 that used open-aeration and chlorine as oxidations, was most effective in removing iron and manganese. In the end, the WTP couldn't diminish the parameters completely and need subsidiary units.

Environmental risk assessments of multiclass pharmaceutical active compounds: selection of high priority concern pharmaceuticals using entropy-utility functions.

This research aimed to identify high-risk pharmaceutically active compounds (PhACs) by analyzing occurrence (O), persistence (P), bioaccumulation (B), and toxicity (T) of 62 drugs which are widely used in Iran. A comprehensive approach was taken in risk assessment of the selected PhACs and in their prioritization using multiple-criteria decision analysis (MCDA) such as utility functions and principal component analysis (PCA). In practice, assigning weight to each criterion (i.e., O, P, B, and T) for risk assessment of PhACs is a challenge. In this research, the impact of giving both equal and unequal weight to each criterion by using a quantitative entropy method was studied. For risk assessment, two exposure approaches (consumption rate and occurrence of PhACs) and three MCDA approaches (PCA and utility functions with and without equal weights for each criterion) were compared. The utility function using equal weights for all O, P, B, and T criteria showed that thioridazine, pimozide, chlorpromazine, sertraline, clomipramine, and aripiprazole were at the highest level of risk, with concern score of 0.75, 0.75, 0.67, 0.58, 0.58, and 0.58, respectively. Unequal weight approach included additional compounds such as fluoxetine, citalopram, and methadone as a priority. All three MCDA approaches showed that sedatives and antidepressants were prevalent PhACs in the risk-based priority lists. However, the exposure-based approaches showed antibiotics and analgesics as the pharmaceutical of the highest priority. Overall, selection of the high priority concern pharmaceuticals depends on the prioritization approach employed. However, the utility function using unequal weights is a more conservative and effective approach for prioritization.

Facile green synthesis of zero-valent iron nanoparticles using barberry leaf extract (GnZVI@BLE) for photocatalytic reduction of hexavalent chromium.

In this study, zero-valent iron (GnZVI) was synthesized using barberry leaf extract (GnZVI@BLE). The physicochemical properties of the final products were characterized by FT-IR, SEM, TEM, and EDS techniques. The results of TEM analysis showed that the obtained iron zero-valent nanoparticles with a diameter between 20 and 40 nm and shell-core structures were successfully synthesized. The results of FT-IR confirmed the presence of various functional groups. The photocatalytic activity of synthesized nanoparticles was investigated by reduction of hexavalent chromium. Laboratory data showed that the presence of GnZVI@BLE as a nanocatalyst in the photocatalytic process could be reduction the hexavalent chromium (Cr (VI)). Photocatalytic data revealed that, when the dosage of nanoparticles was 0.675 g/L, the reduction efficiency of hexavalent chromium was 100%. The kinetics of the reaction follows a pseudo-second-order equation. The constant of reaction rate was 0.4 at pH 2 and 0.5 g/L concentration of GnZVI@BLE.

Chlorpyrifos remediation in agriculture runoff with homogeneous solar photo-Fenton reaction at near neutral pH: phytotoxicity assessment.

This study represents the first application of Fe-citrate-based photo-Fenton chemistry for the degradation of chlorpyrifos (CPF) spiked into agricultural runoff, and its phytotoxicity assessment. The effects of the initial CPF concentration, time and ratio of Fe-citrate/H2O2 on CPF removal during the photo-Fenton reaction were investigated and modeled with analysis of variance using R software by the response-surface methodology package. According to the stationary point in original units, the optimal condition for 70.00% CPF removal was as follows: CPF = 2.5 mg L-1 (0.0), time = 48.0 min (0.585) and Fe-citrate/H2O2 = 0.075 (0.539). Beside running the system at near-neutral pH, another strength of this study is related to the treatment of agricultural runoff contaminated with CPF with a raceway pond reactor, which has the advantages of simplicity of the facilities and procedures, as well as the possibility of using sunlight more efficiently in the field of applications. Finally, untreated and treated agriculture runoffs were used as irrigation to determine their phytotoxic effects on seed germination of cress (Lepidium sativum). Solar photo-Fenton treatment greatly reduced phytotoxicity of agriculture runoff and showed the highest germination percentage (70%) compared to both raw agricultural runoff (60%) and untreated CPF-spiked runoff (35%).

Performance evaluation of ozonation for removal of antibiotic-resistant Escherichia coli and Pseudomonas aeruginosa and genes from hospital wastewater.

The performance of ozonation for the removal of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) using Escherichia coli and Pseudomonas aeruginosa carrying ARGs from hospital wastewaters was evaluated in this study. Bacterial inactivation was determined using plate count methods and real time PCR for ARG damage (Sul1, blatem, blactx, blavim and qnrS). The reduction rate of bacterial cells and ARGs was increased by different amounts of transferred ozone dose from 11 to 45 mg/L. The concentration of 108 cfu/ml bacteria was reduced  to an acceptable level by ozone treatment after a 5 min contact time,  Although the removal rate was much higher for concentrations of 106 cfu/ml and 104 cfu/ml bacteria. Overall, the tendency of gene reduction by ozonation from more to less was 16S rRNA > sul1 > blatem > blactx > qnrS > blavim. Given that plasmid-borne ARGs can potentially be transferred to other bacteria even after the disinfection process, our results can provide important insights into the fate of ARGs during hospital wastewater ozonation.

Synthesis and characterization of SnO2 crystalline nanoparticles: A new approach for enhancing the catalytic ozonation of acetaminophen.

A novel sol-gel method was employed in this study to efficiently synthesize SnO2 nanoparticles to catalyze the ozonation of acetaminophen (ACT) from aqueous solutions. The influence of various parameters including Sn source, type of capping and alkaline agents, and calcination temperature on the catalytic activity of the SnO2 preparations was investigated. The SnO2 nanoparticles prepared by tin tetrachloride as Sn source, NaOH as gelatin agent, CTAB as capping agent and at calcination temperature of 550 °C (SnNaC-550) exhibited the maximum performance in the catalysis of ACT. The optimized catalyst (SnNaC-550) had spherical-homogeneous and cubic-shaped nanocrystalline particles with 5.5 nm mean particle size and a BET surface area of 81 m2/g, which resulted in 98% degradation and 84% mineralization of 50 mg/L ACT at 20 and 30 min reaction time, respectively when combined with ozonation (COP). Based on the radical scavenger experiments, •OH was the major oxidizing agent involved in the removal of ACT. LC/MS analysis showed that short-chain carboxylic acids were the main intermediates. Furthermore, the SnNaC-550 catalytic activity was preserved after four successive cycles. Collectively, the new method has the potential to efficiently synthesize stable and reusable SnO2 nanoparticles to catalyze the ozonation of ACT from aquatic environments.

Associations between short term exposure to ambient particulate matter from dust storm and anthropogenic sources and inflammatory biomarkers in healthy young adults.

This study examined the association between particulate matter from anthropogenic and natural sources and inflammatory biomarkers, including hs-CRP, IL-6, sTNF-RII, and WBCs, in two groups of healthy young subjects. We followed up subjects of two panels (16 to 22 years old), including 22 subjects selected from the urban area (Tehran city) with high-level pollution background and 22 subjects selected from the rural area (Ahmadabad) with low-level pollution background. In each group, we collected 4 times blood samples in various air pollution conditions, In the subjects of the urban group, there was a substantial difference (p < 0.05) between inversion days and cold season control days, and between dust storm days and warm season control days for concentrations of hs-CRP, IL-6, and WBCs biomarkers. In the subjects of the rural group, a significant difference could be detected in the concentration of hs-CRP, IL-6, and WBCs biomarkers (p < 0.05) between inversion days and cold season control days, and between dust storm and warm control days. We found that the difference in concentrations of hs-CRP, IL-6, and WBCs biomarkers between dust storm days and warm control conditions in the rural group were higher than the difference in inversion and cold control conditions, which can be attributed to low background air pollution in the rural area. In the urban area, the health effect of anthropogenic sources of PM is higher than the dust storm condition, which can be attributed to the stronger effect of anthropogenic pollution effect.